Fluid pressure brake apparatus



March 22, 1949. A T GQRMAN 2,464,977

FLUID PRESSURE BRAKE APPARATUS Filed Nov. 13, 1947 2 Sheets-Sheet 1`March 22, 1949.

Filed Nov. 13, 1947 T. GORMAN FLUID PRESSURE BRAKE APPARATUS 2Sheets-Sheet 2 FIGA ' IN V EN TOR. ANDREW T GORMAN ATTORNEY PatentedMar. 22, 1,949

lso srAs far-ur oeFFlcE Claims.

This invention relates to fluid pressure brake apparatus and moreparticularly to the type for use on railroad locomotives.

In U. S. Patent 2,173,940 issued on September 26, i939, to E. Hewitt etal., there is disclosed a locomotive brake equipment embodying anengineers automatic brake valve device for controlling the brakes on'the locomotive and cars of a train either on the straight air principalthrough the medium of train Wires and magnet valve devices on thelocomotive and each car of the train or on the usual automatic principalthrough the medium of a brake pipe and pneumatic brake controlling valvedevices on the locomotive and on cach car of the train. An independentbrake valve device is also provided on the locomotive for controllingthe brakes on the locomotive independently of the brakes on the trainthrough the medium of an interlock valve device associated with thebrake controlling valve device on the locomotive.

The interlock valve device comprises two double Check valves `forselectively closing the automatic, straight air and independent brakecontrol communications to a iiuid pressure relay valve device which isoperative to regulate the brake applying or fluid in the usuallocomotive brake cylinder device according to the controlling pressurein the effective one of said communications. The interlock valve devicefurther comprises an independent release valve for releasing toatmosphere fluid under pressure from the duid pressure relay valvedevice to release the locomotive brakes or to prevent an applicationthereof, and a selector valve device controlled by and cooperative withcngineers independent brake valve device ior controlling said releasevalve device.

The release valve device is in the form of a valve piston arranged tocooperate with an annular seat on one side for controlling the fluidpressure release communication from the fluid pressure relay valvedevice to atmosphere. When the release valve piston is seated the areaof the seated side around the seat is open to the fluid pressure relayvalve device While that Within said seat is open to atmosphere. Whenunseated the ea of the one side of the release valve piston eject topressure ci fluid from the fluid pressure relay valve device. At theopposite side or" the release valve piston is a control chambercontaining a spring for urging the valve to its A small charging portthrough the release valve piston constantly connects the control chamberat the one side to the opposite side outside oi the annular seat. Whilenot disclosedv in the above mentioned patent, the commercial structure`is also provided with another charging communication for the vcontrolchamber in the form of a plurality of ley-pass grooves `for connectingsaid chiarriber to the outside of the 'alhnul-ar seat at ytheoppositeside of the valve piston ivhenthe valve piston -is seated. Thisother coinmunication through the byepass grooves is however closedimmediately upon movement of `the release valve piston from its seat.

The selector valve device is controlled through an actuating pipe fromthe independent 'brake valve devie for controlling communication'betivee'n the control chamber at the one side of the release valvepiston and an application and release pipe extending from end to end ofthe locomotive for connection with a corresponding pipe'ori-aconnected'locomotive or locomotive unit when coupled therewith. Theapplication and re'- lease pipe is also connected to the independentbrake valve device on the respective locomotive.

The independent brake valve device comprises a handle having tvvo planesof movement. In an 'elevated'plane duid under pressure is released fromthe actua-ting pipe to effect movement of the selector valve device to anormal position ier'cls'- ing communication between the control chamberat the one side of the release Vvalve piston andthe application andrelease pipe to permit prompt equalization of duid pressures at oppositesides of said piston to hold it seated while the automatic brake valvedevice is operated "to effect leither an automatic or anelectro-pneumatic straight air application of brakes, so that ythelocomotive brakes Will operate in harmony With those on a connectedtraini Also in this plane ofnovey ment the locomotive brakes may, ifdesired,y be applied and released indelendeI-ltly Oi the train brakeswhen the train brakes are released.

In the depressed plane of movement of the independent brake valvelrldlfluid uhd prs# sure is supplied to' the' actuating pipe to effectoperation of the selector valve device to a release position for'connecting the control chamber at the one side of the release valve.piston to the application and release pipe, and in this plane ofmovement the handle has al `release position for opening's'aid pipe toatmosphere and a locking position for closing communication between saidpipe and atmosphere. The release position, in which the application aridrelease pipe and 'll- 'trol chamber at the one side ofthe release valvepiston are open to atmosphere, is provided` for releasing from saidAc'ont-i'ol chamber fluid under DI'S'SUI Supplied thiltofl'lom th' DDSSlid of the release valve piston through the charging port and/orby-pass grooves, after an application of brakes has been effected, orduring the time uid under pressure is being supplied to the fluidpressure relay valve device, to cause opening of said release valvepiston for releasing fluid under pressure from the fluid pressure relayvalve device for in turn releasing, independently of the train brakes, abrake application already effected on the locomotive, or for preventingan application of the locomotive brakes while the train brakes are beingapplied.

The locking position of the independent brake valve handle is providedfor preventing a straight air application of the locomotive brakes, butnot an automatic application, upon operation of the automatic brakevalve device to apply the brakes on the train. To accomplish this theselector valve when it operates in response to depression of theindependent brake valve handle intercepts the straight air controlcommunication through which a straight air application of brakes on thelocomotive is effected, while the control chamber at the one side of therelease valve piston is merely open to the application and release pipewhich is closed at the independent brake valve device, so that in caseof an automatic application, fluid under pressure supplied to operatethe uid pressure relay valve device will equalize into said chamber andpipe and hold the release valve piston seated to permit the locomotivebrakes to be applied.

When several locomotives or locomotive units are coupled together fordouble or multiple heading, the application and release pipe and theactuating pipe are both connected therebetween, and on each locomotiveor unit, except that selected for control, a double heading cock isoperated to close communication from the respective application andrelease, and actuating pipes to the respective independent brake valvedevice. On all of the connected locomotives or units the control chamberat the one side or the release valve piston is open through theconnected application and release pipe to the independent brake valvedevice on the control locomotive, and also the selector valve devices onthe several locomotives or units are likewise opened through theconnected actuating pipes to the independent brake valve device on thecontrol unit. With this arrangement it is impossible, in an acceptablemanner, to either prevent the brakes on the locomotive or units thereofapplying while applying the train brakes automatically, or to effect arelease of brakes on the locomotives after an application thereof inunison with an application of brakes on the cars of a train.

More specifically, if the engineer on the control locomotive or unitdesires to prevent the brakes on the locomotives or units thereof fromapplying at the time the automatic brake valve device is operated toeiect an automatic application of brakes on the train he will depressthe handle of the independent brake valve device to effect on each ofthe several locomotives or units, operation of the selector valve deviceto its release position for opening the control chamber at the one sideof the release valve piston to the application and release pipe, theconnected application and release pipes on the several locomotive unitsbeing open to atmosphere at this time through the independent brakevalve device on the control locomotive or unit. The operation of thebrake controlling valve device on each of the several locomotive units,in response to operation of the automatic brake valve device, willsupply fluid under pressure to the respective fluid pressure relay valvedevice and the seated side ci the release valve piston. This supply willinitially be very rapid, as a result of which, it will promptly move therelease valve piston against the opposing pressure of the spring in thecontrol chamber and thereby start releasing fluid under pressure beingsupplied to the fluid pressure relay valve device for preventingoperation thereof to apply the locomotive brakes, as desired. However,at the same time, fluid under pressure will i-low from the unseated sideof the release valve piston to the control chamber at the opposite side,this occurring on each locomotive, due to which, and to the longapplication and release pipe connected through the sev.. eral units andwhich is open to atmosphere only at the control locomotive, the pressureof fluid in the several control chambers Iwill build up sufiiciently topermit the spring therein to seat the release valve piston. This closingof the release valve pistons will open the by-pass grooves and provideeven greater flow to the control chambers and to the application andrelease pipes and maintain a pressure therein sufficient to preventreopening of the release valve pistons, with the result that thelocomotive brakes Will apply when it is not desired.

On the other hand, if the locomotive brakes have been applied along withthose on the train, under which condition, on each locomotive thecontrol chamber at the one side of the release valve piston and thepassage connecting said chamber to the selector valve device will befully charged with fluid from the fluid pressure relay valve device, andthe engineer desires to release the locomotive brakes independently ofthose on the train, he will depress the independent brake valve handleto cause operation of the selector valve devices to their releaseposition for opening the several control chambers to the respectiveapplication and release pipes which are connected together and open toatmosphere only at the independent brake valve device on the controllocomotive. The pressure of fluid in the several control chambers willthen suddenly reduce into the application and release pipes and permitunseating of the respective release valve pistons for releasing iluidunder pressure from the respective uid pressure relay valve devices forinitiating the release of the brakes on the respective locomotive.However, with the release valve pistons unseated fluid under pressurewill flow through the ports therein into the control chambers, and dueto the resistance to dissipation of iiuid under pressure therefromthrough the application and release pipes and the single independentbrake valve device on the control unit, suicient pressure will beobtained in said control chambers to reseat the release valve pistonsand thus hold on the several locomotives a partial application of thebrakes, which is not desired,

In either of the above cases, the locomotive brakes can however be fullyreleased by pumping the handle of the independent brake valve device onthe control locomotive between its elevated and depressed positions. Thehandle will be depressed until the release valve pistons seat as abovedescribed and then allowed to return to its elevated plane of movementto effect operation of the several selector Valve devices to disconnectthe respective control chambers from the application and release pipes.The application and release pipes will then become completely ventedcylinders.

can be depressed again to cause local venting of the control chambers tothe vented auxiliary application and release pipes for eiecting anotherrelease of iiuid from the brake cylinders on the locomotive units. Whenthe release valve pi.,- tons then reseat as above described, theindependent brake valve handle can again be allowed to Areturn to itselevated position for completely releasing the application and releasepipes, and then again depressed for effecting a still further vreleaseof fluid under pressure from the control chambers and thereby from thelocomotive brake By continuing this pumping movement of the independentbrake valve handle the locomotive brakes can be released, but eiecting arelease in this requires time and permits the locomotive brakes to be onwhen not intended, and therefore is not desirable.

The principal object of the invention is therefore the provision of animproved interlock valve device arranged to be associated with the brakecontrolling valve device on the locomotive for obviating the abovedifficulty.

According to this object the improved interlock valve device embodies apositively operative local release valve device in place oi the inde`pendent release valve piston above described, and a different selectorvalve device, the parts being so vdesigned and arranged that under allconditions of operation, as controlled by the independent brake valvedevice on the respective locomotive,` or on another locomotive in caseof double or multiple heading, an application of locomotive brakes willbe positively prevented when an application is not desired, and acomplete release oi an application will be promptly obtained wheneverthat is desired.

Other objects. and advantages of the invention will become apparent fromthe following more detailed description thereof.

.cams contained in and arranged in projected relation to variousoperating positions of the handle in said brake valve device; and Fig. 4is an enlargement of a sectional view of a portion of a brakecontrolling valve device shown in Fig. i.

Description As shown in the drawing, locomotive brake equipmentcomprises a brake controlling valve device l, a fluid pressure relayvalve device 2 ar- .'ranged to be controlled by pressure of fluid in acontrol pipe 3 for providing fluid at a corresponding pressure in thebrak-e cylinder device il,

auxiliary reservoir 5, an emergency reservoir 6, an engineers`independent brake valve device .l and a double heading cock 3. All ofthese structures may be identical to corresponding parts fully disclosedin the Hewitt et al. patent above referred to, with the exception of aninterlock valve device 9 forming a part of thev brake Acontrolling valvedevice and which embodies the invention.

The brake controlling valve device l comprises ya pipe bracket l@ uponone face of which is mounted a service application valve device ll,

Cai

while on another face is mounted an emergency valve device l2 along withthe interlock valve device 9. Reference numeral i3 designates the usualbrake pipe adapted to extend from end to end of the locomotive forconnection with the brake pipe on a connected locomotive or locomotiveunits and with the brake pipe on a train and the pressure in which isarranged to be controlled by operation of an engineers automatic brakevalve device, not shown in the present application. The serviceapplication valve device l l is adapted to operate in the usual mannerupon a service reduction in pressure in brake pipe it for supplyingfluid under pressure from the auxiliary reservoir il to an applicationpassage M in the interlock valve device 9 for effecting a serviceapplication of brakes in a manner which will be more fully explainedhereinafter. Upon an emergency reduction in pressure in the brake pipei3 the service application valve device II and emergency valve device i2are both adapted to operate in the usual manner to supply fluid underpressure from the auxiliary and emergency reservoirs ii d to theapplication passage I4 for effecting an emergency application of brakes.Upon rechargino ci brake pipe i3 to its normal pressure, followingeither a service or an emergency application of brakes, the serviceapplication valve device ll and emergency valve device i2 are adapted toreturn to normal position in which the application passage le will bevented to atmosphere.

The reference numeral lli designates a straight air pipe adapted toextend from end to end of the locomotive for connection with thecorresponding pipe on a connected locomotive and/or cars ol a train. Thestraight air pipe lll is connected to a straight air application andrelease passage l in the interlock valve device 9 and the locomotivebrakes will be applied and released in accordance with variations inpressures in said pipe, in a manner to be later described.

The interlock valve device 9 comprises two like double check valves l?and i8 each slidably mounted in a bushing it secured in the casing. Thedouble check valves il and i3 may be like those disclosed in U. S.Patent 2,3ll,85l issued on iebruary 23, 1943, to G. T. McClure, but forthe purpose of illustration are shown in the form of solid cylinders.

The casing is provided with an annular cavity 3E encircling each bushingi9 and each bushing adjacent its opposite ends is provided with aplurality oi through radial ports 33.

The double check valve il is arranged to control communication betweenthe respective annular cavity and the automatic application passage illopening through a seat 3o to one end thereof and a passage ill openingthrough a seat 26 to its opposite end, When iiuid under pressure issupplied to passage lll such pressure acting on the check valve ll isadapted to shift said check valve to the position shown in the drawingto close communication between the respective annular cavity EL. andpassage 3@ and for opening said cavity to passage lll through the ports33 at the lower end of the respective bushing i3. When fluid underpressure is supplied to passage 34 such pressure is adapted to shiftcheck valve Il into contact with the seat 30 to close communicationbetween the respective annular cavity 3i! and the automatic passage l@and for opening said cavity to the passage 34.

The double check valve `lil operates in a like .manner Vto ycontrolcommunication between the respective annular cavity 32 and passages 36and 37|, passage 31 being permanently connected through a passage 38 inthe pipe bracket l and a passage 39 to the annular cavity 32 in thedouble check valve device I1.

The interlock valve device 9 further comprises a selector valve device49 comprising a slide valve 4| which is contained in a chamber 42adapted to be constantly supplied with fluid under pressure from theusual main reservoir on the locomotive through a passage 43. The slidevalve 4| is mounted between two spaced shoulders G4 provided on anoperating stem 45 to one end of which is connected a piston i6 subjectto pressure of uid in chamber d2 for urging said slide valve in thedirection of said piston to the position in which it is shown in thedrawing.

The piston i6 is slidably mounted interiorly of a cylinder G1 providedat one end with a flange 48 clalnped between the casing of the interlockvalve device and a cover G9, said flange and cylinder separating thevalve chamber [i2 from a chamber 50 which is open to atmosphere througha port 5 I. A cup shaped piston 52 slidably mounted in the cover 49 hasguidable contact with the exterior surface of cylinder il and is subjecton one side to atmospheric pressure in chamber B and on the oppositeside to pressure of fluid in a chamber 53 which is open through apassage 55 to an actuating pipe 55. The pipe 55 is connected to theindependent brake valve device 'i and extends from end to end of thelocomotive for connection with a corresponding pipe on anotherlocomotive or locomotive unit when double or multiple heading. Thepiston 52 is ci greater diameter than piston 46 and when subjected topressure of iiuid in chamber 53 is adapted to act through the piston 46and stem G5 for moving the slide valve 4| to a release position, to belater described. Upon release of uid pressure from chamber 53 thepressure of fluid in valve chamber [i2 acting on piston 46 will actuatesaid piston to move the slide valve 4| to the normal position in whichit is shown in the drawing.

The structure embodying the cylinder '57, ange 48, piston 46 and piston52 constitutes the subject matter of an application of Robert E. Watson,Serial No. 749,677, led May 22, 1947, and assigned to the assignee ofthe present application, and is not a part of the present invention.

The interlock valve device 9 further comprises an independent releasevalve device 26. The independent release valve device 29 comprises arelease valve 2| contained in a chamber 56 which is connected by apassage 5ll to the annular cavity 32 around the double check valve i8and thence through a passage 5B to pipe 3 leading to the fluid pressurerelay valve device 2. A spring 53 contained in chamber 56 acts on therelease valve 2| for urging it into contact with a seat 60 for closing abrake release communication between said chamber and a passage 6|encircled at one end by said seat and opening at the opposite end to achamber 62 which is open to atmosphere through a passage 63.

The release valve device further comprises a flexible diaphragm 6darranged in coaxial relation to the valve 2| and subject on one side topressure of fluid in a control chamber 65 which is connected by apassage (i6 to the seat of the selector slide valve 4|. At the oppositeside of diaphragm 64 is a pressure chamber 67 connected by a passage 68to the seat of slide valve 4| and also connected to passage 66 through achoke 69. A follower 19 disposed in chamber 67 in engagement with thediaphragm 64 has a stem extending through said chamber and a wall '|2into chamber 62 and thence through passage 6| for engagement with therelease valve 2|, said stem being of smaller diameter than said passage.A spring '|3 contained in chamber Si and acting on the follower 10 isarranged to normally urge said follower and the diaphragm 66 to the.position in which they are shown in the drawing defined by contact witha stop 'i4 in the casing. In this position of the stem 'Il it is spacedfrom the release valve 2| to permit seating thereof by spring 59. Uponsupply of uid under pressure to chamber 65, in a manner to be laterdescribed, the diaphragm 64 is adapted to deect and move the follower 19and stem 7| -against spring 13 into contact with the release valve 2|and then upon further movement unseat said valve from the seat 60. Asealing ring 15 carried by the stem in the wall '.'2 has sealing andsliding contact with the bore therein for preventing leakage of fluidunder .pressure from chamber 67 to chamber 62 and thence to atmosphere.

Passages l5, 31| and 36 in the interlock valve device also extend to theseat of the selector slide valve 4| as well as a passage 7E which isconnected through the pipe bracket l@ of the brake controlling valvedevice l to an application and release pipe leading to the independentbrake valve device The application and release pipe Tl also extends toopposite ends of the locomotive for connection with the correspondingpipe on another locomotive or locomotive unit in case of double ormultiple heading.

Since the independent brake valve device 1 is the same as disclosed inthe aforementioned Hewitt patent the following description thereof willbe limited to only that deemed essential to a clear understanding of theinvention.

The independent brake valve device 2 is provided for controlling thebrakes on the locomotive independently of the brakes on the cars in atrain and comprises a casing in which there is disposed a spindle 18which is rotatable by a handle 19 for controlling operation of aselflapping application and release valve mechanism 89 and of a cut-offvalve 8|, while a lockout valve mechanism 92 is provided in said casingfor control by said handle in all positions thereof, independently ofmovement of said spindle. A pivot pin 83 connected to -a sleeve 84having driving engagement with spindle '|8 is provided to permitvertical movement of handle 19 relative to said spindle. A spring 85contained in the sleeve 86 acts on the handle '|9 for turning it aboutthe pin 83 to a normal elevated position, in which it is shown in thedrawing, and for opposing downward manual movement of said handle.

As viewed in Figs 2 and 3 of the drawing, the brake valve handle 'I9 isprovided with a locking position to the extreme left, a release positionto the immediate right thereof and in which the handle is normallycarried (Fig. 2) and an application and release Zone extending towardthe right-hand from the release position.

The self-lapping application and release valve mechanism 89 comprises anapplication valve 86 for controlling communication between a chamber 81in which the spindle 'I8 is disposed and a passage 88 which is connectedto a fluid pressure supply pipe 89. The valve 86 is carried by a plunger99 slidably mounted in a suitable bore in the casing and containing aspring 9| acting on said plunger for urging said valve to its seatedposition.

A lapping piston 92 is slidably mounted in a suitable bore in the casingand is open at one side to chamber 8'! and at the opposite side to achamber 93 which is in permanent communication with atmosphere through apassage lill and which contains an adiustable control spring S acting onthe piston 92 for urging it in the direction of chamber 8l.

The lapping piston 92 is provided axially with a chamber Q5 open tochamber 8l and containing a release valve Ell for controllingcommunication between chamber il and the atmospheric chamber 93. Therelease valve @l is provided with a stern the outer end of whichslidably extends through a suitable opening in an element @il secured tothe left-hand face oi the piston Q2. An annular collar SS is provided onthe release valve stem at the riglit-hand side of element S8 forengagement therewith to limit unseat-ing movement of the re lease v-alverelative to the piston 92, a spring I5@ provided in .piston actson saidcollar for urging said valve to its open position.

A plunger lil! contained in chamber 8l has one end slidably mounted in asuitable casing bore arranged parallel to and intermediate the axes ofthe Iapplication valve 86 and release valve Q'i. The opposite end ofplunger I @I is disposed in operative alignment with a cam Iii-2 carriedthe brake valve spindle le. A rocking beam i133 is pivotally connectedintermediate its ends to the plunger IGI. In one end of this bea-rnthere is provided a roller Iii!! for engaging the end of the releasevalve stem, while llivotally connected to the other end is one end of apin i535 the other end of which engages the application valve et withina suitable axial recess.

The cam |ll2 is arranged to urge the plunger IDI outwardly, that istoward the right-hand as viewed in the drawing, upon movement of thehandle 'I9 from its release position into the application and releaseZone and to permit return of said plunger to the position in which it isshown in the drawing upon return of said handle to release position, thedegree of movement of said plunger from the position shown in thedrawing depending upon the distance the handle is moved from releaseposition. The operating surface of the cam Iil2 is of constant radiusbetween the release and locking positions of the handle 'I9 so that uponmovement between these positions plunger m2 will remain stationary.

A cam |06 is associated with the cam |52 for controlling operation ofthe cut-off valve 8|. The cut-ofi valve Si is contained in a chamberIll'l open to the application and release pipe 'I1 and is provided witha iluted stem i553 slidably` mounted in a suitable bore connectingchamber lill to chamber 87 and extending through said bore into thelatter chamber into operative alignment with the cam lt.

lill acts on the valve 3l for urging it to its seat. The cam It@ is sodesigned as to permit seating oi the valve 8l in the locking position ofhandle 'lil but to eiect unseating of said valve upon movement of saidhandle to release position and to maintain said valve unseated in theapplication and release zone, as will be clear from an inspection ofFig. 3 of the drawing.

The lockout valve mechanism 82 comprises two oppositely seating valvesIl@ and III disposed in chambers iii and lit, respectively, and providedwith oppositely extending ilu-ted stems which kengage each other in anintermediate chamber IM. The chamber Il? is connected to the fluidpressure supply pipe 89 and contains a spring ||5 for the A spring H39in chamber .l

seating the valve I IIl and for at the same time unseatingvalve III. Thechamber Il3 is open to atmosphere through a passage H8, while theintermediate chamber I I4 is connected to the actuating pipe 55.

The brake valve device further comprises a substantially semi-circularbail III pivoted on a pin IIS and having a portion disposed over theaxes of the valves Il@ and III. Interposed between the valve I I and thebail I I'I is a spring seat ||9 engaging said valve, a plunger |20engaging said bail and a pair of interposed springs I2| and |22 arrangedin tandem. With the handle 'I9 supported in its elevated position byspring 85 the springs IZl and 122 will be suiliciently extended topermit closing of valve IIli and opening of valve III by spring H5, butupon depressing of the handle lS against the spring 85 the pressure ofsprings l2| and |22 will be increased to a degree exceeding that ofspring I5 so as to close valve I l I and open valve IIB.

A removable handle guard I 23 is secured to the top of the brake valvecasing and is provided in one side with an opening |24 extendingcircumferentially thereof in which the brake valve handle lil is adaptedto move to its different positions, the length of this opening beingsufcient to permit such movement.

The upper edge of this opening |24 against which the handle 'I9 isnormally forced into engagement by spring 85 is however formed at threedifferent levels, ther-e being a portion |25 and to the left thereof twosuccessive downward steps.

I 26 and I2?, The portion |25 is coextensive with the application andrelease zone and is of such length as to permit the handle 'I9 to beheld in its raised position by spring 85 in the release position thereofand in the application and release Zone. In order to move the handle tothe left from release position to the locking position defined by stepI2l, it must be depressed a certain amount in order to move in under thestep |26 and then it must be further depressed to move in under the step|271. It will be noted that upon release of manual pressure on thehandle 'I9 the spring t5 will urge said handle into engagement with thestep |21 which is made concave to receive said handle and thus preventsaid handle slipping out of said position.

Upon movement of the handle 'I9 from release position to lockingposition, the downward movement thereof and of bail I Il will act toseat Valve I I l and open valve I I5, while the cam |06 will be .i sopositioned as to permit closure of valve 8| by spring |09. In all otherpositions of the brake valve handle I9 the valve 8| will be opened bycam Iill. It will be noted that in the release position and in theapplication and release zone the handle IS may also be depressed forclosing valve III ,and opening valve Il but the cut-off valve 8| willremain open during such operation.

The double heading cock 8 controls communication between the independentbrake valve device l .and the actuating pipe and application and releasepipe ll. This cock is carried in open position for establishingcommunication between the independent braise valve device and thesepipes on the control locomotive in double or multiple heading, and whenonly a single locomotive is connected to control a train. On all 100,0.-motives except the control locomotive in double or multiple heading thedouble heading cock 8 is however moved to a closed position fordisconnecting the yapplication and release pipe and 11 the actuatingpipe 55 from the respective independent brake valve device.

Operation In operation, let it be initially assumed that the engineerdesires the brakes on the locomotive to operate in unison with those ona connected train, as controlled through the medium of either thestraight air pipe I or the brake pipe I3. To accomplish this the handle19 of the independent brake valve device 1 will occup-y its elevatedrelease position in which it is shown in the drawing for opening theapplication and release pipe 11 to atmosphere past the open cut-offvalve 8|, chamber 81 and exhaust valve 91, and for at the same timeopening the actuating pipe 55 to atmosphere past the open valve |II.With the actuating pipe 55 and thereby piston chamber 53 in theinterlock valve device 4D open to atmosphere pressure of fluid in slidevalve chamber 42 of the selector valve device acting on piston 46 willactuate said piston and the piston 52 to the position in which they areshown in the drawing for correspondingly positioning the said selectorlslide valve 4|. With the slide valve 4| in this position chamber 65above diaphragm 64 in the release valve device 54 will be open toatmosphere through passage 66, a cavity |28 in said slide valve and anatmospheric port |29, while chamber 61 below said diaphragm will also bevented by Way of passage 68, choke 69 and the vented passage 66. Withthe opposite sides of diaphragm 64 thus both subject to atmosphericpressure spring 13 will elevate the diaphragm 64 to the position inwhich it is shown in the drawing for thereby drawing stem 1| away fromthe release valve 2| to permit closing of said valve by spring 59. Withthe selector slide valve 4| in the normal position just described theupper end of the double check valve I8 will be open to atmospherethrough passage 36, a cavity in said slide valve, passage 16 and thevented application and release pipe 11, while the upper end of thedouble check valve I1 will be connected to the straight air pipe I5 byway of passage 34, a cavity |3| in the selector slide valve 4| and thepassage I6.

Now let it be assumed that the operator desires to apply the brakes onthe locomotive through the medium of the straight air pipe I5 in unisonwith the brakes on a train also controlled through said pipe. Toaccomplish this he will supply fluid under pressure to the straight airpipe I5 from whence it will flow through passage |6 to the seat of theselector slide valve 4| and then through cavity |3| in said slide valveto passage 34 leading to the upper end of the double check valve I1. Atthis time passage I4 connected to the lower end of the double checkvalve I1 will be open to atmosphere through the brake controlling valvedevice I as a, result of which pressure of fluid from passage 34 willshift the double check valve I1 to its lower position to closecommunication between the respective annular cavity 32 and passage I4and open said cavity to passage 34. Fluid under pressure from passage 34will then flow through cavity 32 around the double check valve I1, andpassages 39, 38 and 31 to the lower end of the double check valve I8.The upper end of the double check valve device I8 is at this time ventedthrough passage 36, cavity |36 in the selector slide valve 4I, passage16 and the independent application and release pipe 11, so that fluidpressure from the straight air pipe acting on the lower end of thedouble check valve I1 will shift said valve to its upper position toclose communication between passage 36 and the respective annular cavity32 and open said cavity 32 to passage 31 whereupon uid from the straightair pipe in passage 31 will ilow to said cavity 32 and thence throughpassage 58 and pipe 3 to the relay valve device 2 for effectingoperation thereof to supply fluid under pressure to the brake cylinderdevice 4 for applying the brakes on the locomotive.

In order to release a straight air application of brakes on thelocomotive in unison with the release of a straight air application ofbrakes on cars of a train, fluid under pressure will be released fromthe straight air pipe I5, whereupon uid will be released from the uidpressure relay valve device 2 back through the communication justdescribed to said straight air pipe for permitting operation of saidrelay valve device to release uid under pressure from the brake cylinderdevice 4 for releasing the brakes on the locomotive.

Now let it be assumed that through the medium of the brake pipe I3 theengineer desires that the brakes on the locomotive operate in unisonwith those on the train. Upon a reduction in brake pipe pressure fluidunder pressure will be supplied by operation of either the serviceapplication valve device II or said device and the emergency valvedevice I2, depending upon whether the reduction is at a service oremergency rate, to passage I4 leading to the lower end of the doublecheck valve I1. At this time the upper end of the double check valve I1will be vented through the straight air pipe I5, as a result of which,said check valve will shift to its upper position to permit fluid frompassage I4 to flow to the respective annular cavity 32 and then throughpassages 39, 38 and 31 to the lower end of the double check valve I 8.With the upper end of the double check valve I8 vented to atmosphere atthis time through the independent application and release pipe 11, thedouble check valve I8 will be shifted to its upper position to permit owof fluid from passage 31 to the respective annular cavity 32 and thenceto passage 58 connected through pipe 3 to the relay valve device 2. Therelay valve device 2 will thereby be operated to supply fluid to thebrake cylinder device 4 at a pressure corresponding to the reduction inpressure in the brake pipe I3. Upon recharging of the brake pipe I3 andopening of passage I4 to atmosphere through the sen/ice applicationvalve device II, in the usual manner, uid pressure will be released fromthe relay valve device 2 to permit operation thereof to release thebrakes on the locomotive.

It will now be seen that with the independent brake valve handle 19 inits normal release position, in which it is shown in the drawing, thebrakes on the locomotive can be controlled either through the medium ofthe straight air pipe I5 or the brake pipe I3 in unison with the controlof brakes on cars of a connected train. It will also be noted thatregardless of the type of control, uid under pressure supplied topassage 58 for flow to the relay valve device 2 for eiecting operationthereof also flows from the annular cavity 32 around the double checkvalve I8 through passage 51 to the release valve chamber 56 in theindependent release valve device 54 but the valve 2| in said chamber isat this time posi-l tively seated by spring 59 to prevent release ofsuch pressure under these conditions.

With the straight air pipe l vented to atmos.A

phere and the brake pipe i3 fully charged, under which condition thebrakes on the locomotive will be released, if the operator desires toapp-ly the brakes on the locomotive independently of those on the trainhe will operate the handle 79, with out depressing it, from the releaseposition into the application and release Zone. rIhis operation willdisplace the plunger icl so as to rock the lever ills iirst in aclockwise direction about its connecton with the application valve operating stem teli for seating the release valve 97, following which, thesupply valve 813 will be opened, this sequence of operation beingobtained since the pressure of spring lill) on the release valve is lessthan that of spring 9i acting on the supply valve. Upon opening of thesupply valve lll? under pressure supplied thereto from the supply pipewill iiow past said valve into chamber ill and thence past the opencut-- off valve 3l to the application and release pipe 11.

Fluid under pressure thus supplied to the application and release pipell will flow to passage 'I6 in the interlock valve device and thencethrough cavity 39 in the selector slide valve di to passage leading tothe upper end of the double check valve device ill. The lower end of thedouble check valve lll will at this time be open through ges 3l, 3S and39 and the double check valve il to atmosphere either by Way of passagewhich is open to the straight air'pipe i3 or by way of passage i@ in thebrake controlling valve device l Which is in its release position. As aresult, the pressure of fluid supe plied by the inf'lm ident bralzevalve device to passage will shi t the double check valve i8 to itslower seated position whereupon fluid from Said passage will flow to therespective annular cavity 32 and thence through passage 58 and pipe 3'to the relay valve device The relay valve de vice 2 will then operate tosupply ilu-id at a corresponding pressure to the brake cylinder deviceIl for applying the brakes on the locomotive independently of thestraight air pipe l5 and of the brake pipe i3 and thus independently ofthe brakes on the train.

The self-lapping application and release valve mechanism Sii isoperative to vary the pressure of fluid provided in the relay valvedevice 2 and thereby the degree of brake application on the locomotivein accordance with the position of the independent braise cylinderhandle 79 in the ap plication release zone, in a manner which is wellunderstood and which need not be described here in detail, it beingmerely desired to point out that upon return of the brake valve handle79 to its release position the cam mi? will be so positioned as topermit closure oi the supply valve E5 and opening of the release valvel? for releasing i'luid under pressure from the relay valve device 2 andthereby from the brake cylinder de vice l for releasing the locomotivebrake.

Now let it be assumed that the engineer desires to prevent thelocomotive brakes from applying at the time of eflecting an applicationof brakes on the train by either supplying fluid under pressure to thestraight air pip-e l5 or reducing the pressure in the brake pipe i3. Toaccomplish this he will merely depress the handle 'i9 from its releaseposition and thereby close valve lll and open valve lid to supply fluidunder pressure to the actuating pipe and thence to pistonchamber 53'inthe selector valve device` ll, it being noted that the cut-off valve 8lin the independent brake valve device is still open connecting the apeAplication and release pipe ll to atmosphere.

When iluid under pressure is supplied to piston chamber 53 in theselector valve device 40 as i just described, such pressure acting onpiston 52- will overcome the opposing force of pressure of fluid invalve chamber l2 acting on piston l5 andv move said pistons and therebythe slide valve to release position in which passage 66 is disconenected from the atmospheric passage |29 and opened through a port 532 insaid slide valve to the valve chamber 42, whereupon fluid at main.

reservoir pressure from said valve chamber will become eiiective inchamber t5 above the dia-y phragm Elfi. Chamber 6l' below the diaphragm64 will at the same time bc opened to atmosphere through passage Se,cavity lllll in the selector slide valve il to passage lo in turnconnected to.

the vented application release pipe Tl. A portion of the fluid supplied:from the selector valve'` chamber #i3 to passage 55 will flow throughthe choke til to passage @El but will be dissipated through theapplication and release pipe 'I7 at:

this time, so that the pressure of fluid in dia.. phragrn chamber @lwill be reduced to substantially that oi atmosphere and permit pressureof iiuid in chamber Elli to deect the diaphragm 64,

downwardly for operating the stem ll to open the release valve 2 l.

In this upper position of the selector slide valve; lll communicationbetween passage I6 connected to the straight air pipe l5 and passage 34Willbe.

closed so vas to positively prevent supply of fluid under Apressure tothe latter lpassage for effecting an application of brakes on thelocomotivev when Fluid lunder pressure is supplied to the straight airpipe I5 for applying the brakes on the train. However, if the pressure0f fluid in the brake pipe i3 is reduced for electing an automaticapplication of brakes on the train, the brake controlling valve device lwill operate in the usual' way to supply fluid under pressure .topassage l Il through which it will how :to the double check.

ling valve device l on the locomotive to passages:

58 and 5l will therefore be dissipated to yatmosphere and preventoperation of the relay valve device 2 to apply the locomotive brake,whereby` the brakes on the locomotive will be held off while the bra-keson the :train are being applied.

With this type of equipment the brakes onA ay train are usuallycontrolled by straight air through the .medium of the straight air pipel5 and the operator may desire to permanently prevent the brakes on thelocomotive from applying at .the time the brakes on the train areapplied by straight air, but at vthe same time, for thesaiety of `thetrain, ensure that the brakes in the locomotive will apply automaticallyin casel of a reduction in brake pipe pressure due for ins-tance tobreak in two of the train. To accomplish this, the engineer will depressthe handle lll move it to its locking position wherein the-selectorvalve device lo will move toits upper position as just described yand:the cutoi valve lll in the independent brake valve def vice will beseated thereby closing the atmospheric connection to the applicationand; release` pipe 11. With the application and release -pipe 11disconnected from atmosphere by the independent brake valve device asjust described, the supply of uid under .pressure to said pipe by way ofchoke 69, passage 68, cavity |30 in slide valve 4| and passage 'I6 willincrease the pressure there-- in and in said passages and thus indiaphragm chamber 6l of .the independent release valve device 54 to thesame degree as effective in chamber '65 at the opposite side of thediaphragm 64 whereupon spring 'i3 will deflect said diaphragm to theposition in which it is shown in the drawing to permit closure of therelease valve 2|.

With the equipment thus conditioned a straight air application of brakeson the locomotive upon supply of fluid under pressure to the straightair pipe I for applying the brakes on -a train will be prevented for thesame reasons as hereinoefore described, but in case of a reduction inpressure in the brake pipe I3 the fluid under Ipressure supplied by theconsequent operation of the brake controlling valve device I to passageI4 will be prevented from escape to atmosphere since the independentrelease valve 2| is seated, as a result of Which the brakes on thelocomotive will be positively applied.

Now let it be assumed that With handle 19 of the independent brake valvedevice in its elevated release position, that the brakes on thelocomotive have been applied along with the brakes on the train, eitherthrough the medium of supplying fluid under pressure to the straight airpipe l5 or reducing the pressure in the brake pipe I3, and that theengineer desires to release the brakes on the locomotive independentlyof those on the train. To effect this he will depress the handle 'l fromits release position and thereby close the valve III and open the valveIIU in the lockout valve mechanism 82, and as a result supply uid underpressure to piston charnber 53 in the selector valve device 40 andactuate said device .to its upper position for supplying fluid underpressure to diaphragm chamber 65 in the independent release valve device20 and for at the same time 4opening chamber 61 at the opposite side ofdiaphragm 64 .to atmosphere through cavity |38 in the slide valve 4| andthence through pipe T6 and the application and release pipe 'Il which isvented past the open cut-off valve 8| in the independent brake valvedevice. As a result oi venting the fluid under pressure from diaphragmchamber 51 in the independent release valve device 20 the main reservoirpressure provided in diaphragm chamber 65 will deflect said diaphragmand open the release valve 2| for thereby releasing uid under pressurefrom passage 51 and the connected relay valve device 2 for permittingoperation of said relay valve device 2 to effect a release of fluidunder pressure from the brake cylinder device 4 for releasing thelocomotive brake.

It will be noted that in effecting an independent release of the brakeson the locomotive, as just described, there will be a slight flow offluid under pressure through the choke G9 to the application `andrelease pipe which is vented to atmosphere through the independent brakevalve device, the same as occurs in preventing an ap- -plication oflocomotive brakes at the time the brakes on the train are applied, but`this flow is restricted to such a degree that even on a `plurality ofconnected locomotives, such as four or five, such ow at each locomotiveto the application and release pipe 11 will not increase the pressuretherein to any material degree against the single exhaust past thecut-olf valve 8| in the independent brake valve device on the controllocomotive, Whereby the pressure of fluid in diaphragm chamber of therelease valve device on the one or more locomotives will ypositivelyhold the release valve 2| open to either prevent the application oflocomotive brakes or to insure a complete and positive release of anapplication of locomotive brakes, as the case may be, and as desired.The only purpose of choke S9 is for charging the application and releasepipe when the independent brake valve handle 2?: is in locking positionso as to obtain the pressure required in diaphragm chamber 51 on eitherone or several connected locomotives for insuring positive closing ofthe independent release valve 2| for the reasons above described.

In the release position of the selector slide valve l it will be notedthat the passages 34 and 3B are open through cavity |3| to anatmospheric passage B33. The purpose of this is to insure that theressure in these passages will be atmospheric at a time when anautomatic application of brakes is effected with the independent brakevalve device i9 in the locking position, so that the double ch ck valvedevices and I8 will remain in 'their upper position to permit therelease of such an application upon a subsequent increase in pressure inthe brake pipe I3 and consequent operation of the brake controllingvalve device if t ese passages 34 and 36 were not vented under thiscondition, leakage of fluid under pressure past the double check valvesinto said passages while the brakes were applied might, upon opening ofpassage Ill to atmosphere through the Ibrake application valve device Iupon a subsequent increase in brake pipe pressure, -permit the bottledpressure of fluid in either one of said passages to shift the respectivedouble check valve il' or I8 to its opposite seated position from thatoccupied when an automatic application of brakes is effected, and thusprevent release of such an application.

Summary From the above description it will now be seen that I haveprovided a release valve device for preventing an application of brakeson the locomotive or for releasing an application, independently of thebrakes on the train. The independent release valve device controls alocal brake release communication from the fluid pressure relay valvedevice and is controlled by -1 positive opposing forces to insurepositive and prompt conditioning thereof in response to operation of theindependent Ibrake valve device on the respective locomotive, or on thecontrol locomotive in multiple or double heading. Further, the selectorvalve device is so constructed as to positively assure the release of anautomatic application of brakes on the locomotive by operation of thebrake controlling valve device there on in response to an increase inbrake pipe pressure with the independent brake valve handle 19 inlocking position. In locking position of the brake valve handle a chokein the selector valve device provides for charging of the applicationand release pipe as required to condition the independent release valveto permit seating of the release valve 2|. Where a plurality oflocomotives are connected together for operation in multiple the chokeon each locomotive will be effective to charge the application andrelease pipe, but these chokes are of such small ow 17 capacity as tohave no material effect upon operation of the several independentrelease valve devices on the locomotives in response to operation of theoperators independent Ibrake valve handle 19.

Having now described the invention, what I claim as new and desire tosecure by Letters Patent, is:

1. In a locomotive fluid pressure brake equipment, the combination withbrake means operable by fluid under pressure to effect an application oflocomotive brakes and upon release of such iluid under pressure arelease of locomotive brakes, brake control means for supplying andreleasing fluid under pressure to and from said brake means, acommunication for releasing fluid under pressure from said brake meansindependent of said brake control means, a release valve for opening andclosing said communication, movable abutment means controlled byopposing pressure of iluid in two chambers for controlling said releasevalve, and means including an engineers independent lbrake valve devicefor controlling the pressure of fluid in said chambers.

2. In a locomotive iluid pressure brake equipment, the combination withbrake means operable by fluid under pressure to effect an application oflocomotive brakes and upon release of such fluid under pressure arelease of locomotive brakes, brake control means for supplying andreleasing iluid under pressure to and from said brake means, acommunication for releasing fluid under pressure from said .brake meansindependent of said brake control means, a release valve for opening andclosing said communication, movable abutment means operable upon supplyof fluid under pressure t-o one cham-ber to operate said release valveto open said communication, means for operating said release valve toclose said communication upon substantial equalization of pressure offluid in said one chamber with pressure of fluid in another chamber, andmeans including an engineers brake valve device for controlling thepressure of fluid in said'one and other chambers.

3. In a lo-comotive iluid pressure brake equipment, the combination withbrake means operable by fluid under pressure to eiect an application oflocomotive brakes and upon release of such fluid under pressure arelease of locomotive brakes, brake control means for supplying andreleasing iluid under pressure to and from said brake means, acommunication for releasing fluid under pressure from said brake meansind-ependent of said brake control means, a release valve for openingand closing said communication, movable abutment means operable uponsupply of lluid under pressure to one chamber to operate said releasevalve to open said communication, means for operating said release valveto close said communication upon substantial equalization of pressure ofiluid in said one chamber with pressure of fluid in another chamber, anactuating pipe adapted to be connected between locomotives, anapplication and release pipe adapted to be connected betweenlocomotives, a selector valve movable to a normal position upon releaseof fluid under pressure from said actuating pipe to open said chambersto atmosphere and movable to a release position upon supply of fluidunder pressure to said actuating pipe to supply fluid under pressure tosaid chambers, and to connect said other chamber to said application andrelease pipe, means for restricting the supply of fluid under pressureto said other chamber and 18 the connected application and release pipewith respect to the supply of fluid under pressure to said one chamber,and an engineers independent brake Valve device for selectivelysupplying iluid under pressure to and releasing fluid under pressurefrom said actuating pipe and for selectively opening and closingcommunication between said application and release pipe and atmosphere.

4. In a locomotive fluid pressure brake equipment, the combination withbrake means operable by fluid under pressure to eiect an application oflocomotive brakes and upon release of such fluid under pressure arelease of locomotive brakes, brake control means for supplying andreleasing iluid under pressure to and from said brake means, acommunication for releasing iluid under pressure from said brake meansindependent of said brake control means, a release valve for opening andclosing said communication, movable abutment means operable upon supplyof fluid under pressure to one chamber to operate said release valve toopen said communication, means for operating said release valve to closesaid communication upon substantial equalization of pressure of fluid insaid one chamber with pressure of fluid in another chamber, an actuatingpipe adapted to be connected between locomotives, an application andrelease pipe adapted to be connected between locomotives, a selectorvalve movable to a normal position upon release of iluid under pressurefrom said actuating pipe to open said chambers to atmosphere and movableto a release position upon supply of fluid under pressure to saidactuating pipe to supply fluid under pressure to said chambers, and toconnect said other chamber to said application and release pipe, meansfor restricting the supply of fluid under pressure to said other chamberand the connected application and release pipe with respect to thesupply of fluid under pressure to said one chamber, and an engineersindependent brake valve device for opening said application and releasepipe to atmosphere and for at the same time selectively supplying fluidunder pressure to or releasing fluid under pressure from said actuatingpipe.

5. In a locomotive iluid pressure brake equipment, the combination withbrake means operable by fluid under pressure to eiect an application oflocomotive brakes and upon release of such fluid under pressure arelease of locomotive brakes, brake control means for supplying andreleasing fluid under pressure to and Vfrom said brake means, acommunication for releasing vfluid under pressure from said brake meansindependent of said brake control means, a release valve for opening andclosing said communication, movable abutment means operable upon supplyof iluid under pressure to one chamber to operate said release valve toopen said communication, means for operating said release valve to closesaid communication upon substantial equalization of pressure of iluid insaid one chamber with -pressure of fluid in another chamber, anactuating pipe adapted to be connected between locomotives, anapplication and release pipe adapted to be connected betweenlocomotives, a selector valve movable to a normal position upon releaset of fluid under pressure from said actuating pipe release pipe fromsaid brake means and open same to said other chamber, means forrestricting supply of fluid under pressure by said selector valve tosaid other chamber and the connected application and release pipe withrespect to the supply of fluid under pressure to said one chamber, andan engineers independent brake valve device for selectively supplyinguid under pressure to and for releasing fluid under pressure from saidactuating pipe and for selectively opening and closing communicationbetween said application and release pipe and atmosphere.

6. In a locomotive fluid pressure brake equipment, the combination withbrake means operable byuid under pressure to eect an application oflocomotive brakes and upon release of such fluid under pressure arelease of locomotive brakes, brake control means for supplying andreleasing flui-d under pressure to and from said brake means, acommunication for releasing uid under pressure from said brake meansindependent of said brake control means, a release valve for opening andclosing said communication, movable abutment means operable upon supplyof fluid under pressure to one chamber to operate said release valve toopen said communication, means for operating said release valve to closesaid communication upon substantial equalization of pressure of fluid insaid one chamber with pressure of fluid in another chamber, an actuatingpipe adapted to be connected between locomotives, an application andrelease pipe adapted to be connected between locomotives, a selectorvalve movable to a normal position upon release of fluid under pressurefrom said actuating pipe to open said chambers to atmosphere and toconnect said applicatLon and release pipe to said brake means andmovable to a release position upon supply of fluid under pressure tosaid actuating pipe to supply uid under pressure to said chambers and todisconnect said application and release pipe from said brake means andopen same to said other chamber, means for restricting supply of uidunder pressure by said selector valve to said other chamber and theconnected application and release pipe with respect to the supply offluid under pressure to said one chamber, and an engineers independentbrake valve device comprising one valve means for selectively supplyinguid under pressure to and for releasing fluid under pressure from saidactuating pipe, another valve means for selectively opening and closingcommunication between said application and release pipe and atmosphere,an operators control handle, and means operative by said handle forselectively controlling said one and other valve means.

7. In a locomotive fluid pressure brake equipment, the combination withbrake means operable by fluid under pressure to effect an application oflocomotive brakes and upon release of such fluid under pressure arelease of locomotive brakes, a communication for conveying fluid underpressure to and from said brake means, a release valve having a releaseposition for opening said communication to atmosphere and having anormal position for disconnecting said communication from atmosphere,movable abutment means operable by fluid under pressure in one chamberto move said release valve to said release position, means for movingsaid release valve to said normal position upon substantial equalizationof fluid pressures in said one chamber and in another chamber, aselector valve having one position for equalizing the fluidpressures insaid one and other. chambers and another position for supplying fluidunder pressure to said one chamber, and an engineers independent brakevalve device cooperative with said selector valve in its said otherposition to either provide fluid under pressure in said other chamber orto release fluid under pressure therefrom.

8. In a locomotive uid pressure brake equipment, the combination withbrake means operable by fluid under pressure to effect an application oflocomotive brakes and upon release of such uid under pressure, a releaseof locomotive brakes, a brake pipe, brake control means operable upon areduction in pressure in said brake pipe to supply iiuid under pressureto a communication leading to said brake means, a release valve having abrake release position for opening said communication to atmosphere andhaving a normal position for disconnecting said communication fromatmosphere; a movable abutment operable upon supply of fluid underpressure to one'chamber to move said release valve to said releaseposition, means for moving said release valve to said normal positionupon substantial equalization of pressures in said one chamber and in another chamber, an application and release pipe adap-ted to be connectedbetween locomotives, an actuating pipe adapted to` be connected betweenlocomotives, a selector valve having a normal position for equalizingopposing fluid pressures on said abutment and for establishing aconnection for flow of iiuid under pressure between said application andrelease pipe and a passage and having a brake release position forclosing said connection and for opening said passage to atmosphere andfor also supplying iiuid under pressure to said chambers and forconnecting said other chamber to said application and release pipe,means for restricting the supply of fluid under pressure to said otherchamber and application and release pipe in said brake release positionof said selector valve, a double check valve open at opposite ends tosaid brake control means and passage for selectively controllingcommunication therebetween and the rst named communication, and anengineers independent brake valve device for selectively supplying fluidunder pressure to and releasing fluid under pressure from each of saidpipes and for also closing communication between said application andrelease pipe and atmosphere.

9. In a locomotive uid pressure brase equipment, the combination withbrake means operable upon supply of uid under pressure to a passage toeffect an application of locomotive brakes and upon release of fluidunder pressure from said passage a release of locomotive brakes, astraight air pipe for conveying fluid under pressure to andfrom saidpassage, a brake pipe, brake control means operable upon a reduction andincrease in pressure in said brake pipe for, respectively, supplyingfluid under pressure to and releasing fluid under pressure from saidpassage, an application and release pipe, an engineers independent brakevalve device for supplying and releasing uid under pressure t0 and fromsaid passage. by way of said pipe, a double check valve open at oppositeends to said straight air pipe and brake control means for selectivelyclosing communication therebetween and a second passage, another doublecheck valve open at opposite ends to said second passage and saidapplication and release pipe for selectively closing communicationtherebetween and the first named passage, a selector valve having anormal position for opening said straight air pipe and application andrelease pipe to the respective ends of said double check valves andanother position for disconnecting same from said double check valvesand for opening said respective ends to atmosphere, and means forcontrolling said selector valve.

10. In a locomotive fluid pressure brake equipment, the combination withbrake means operable upon supply of iiuid under pressure to a passage toeffect an application of locomotive brakes and upon release of liuidunder pressure from said passage a release of locomotive brakes, astraight air pipe for conveying fluid under pressure to and from saidpassage, a brake pipe, brake control means operable upon a reduction andincrease in pressure in said brake pipe for, respectively, supplyingfluid under pressure to and releasing fluid under pressure from saidpassage, an application and release pipe, an engineers independent brakevalve device for supplying and releasing fluid under pressure to andfrom said passage by way of said pipe, a double check valve open atopposite ends to said straight air pipe and brake control means forselectively closing communication therebetween and a second passage,another double check valve open at opposite ends to said second passageand said application and release pipe for selectively closingcommunication therebetween and the first named passage, a selector valvehaving a normal position for opening said straight air pipe andapplication and release pipe to the respective ends of said double checkvalves and another position for disconnecting same from said doublecheck valves and for opening said respective ends to atmosphere, anactuating pipe connected to said brake valve device, means operable uponsupply of fluid under 22 pressure to said actuating pipe to effectmovement of said selector valve to its said other position and uponrelease of iiuid under pressure from said actuating pipe to said normalposition, 5 a release valve having a normal position for closing anatmospheric connection to said first passage and a release position foropening such connection, movable abutment means operable upon supply ofiiuid under pressure to one chamber to move said release valve to saidrelease position and upon substantial equalization of pressures of fluidin said one chamber and another chamber to effect movement of saidrelease valve to said normal position, said selector valve in its normalposition effecting equalization of fluid pressures in said one and otherchambers and in its other position supplying fluid under pressure toboth of said chambers and to said application and release pipe, andmeans for restricting the supply of fluid under pressure to said otherchamber and application and release pipe with respect to the supply offluid under pressure to said one chamber, said independent brake valvedevice being also operative with fluid under pressure released 25 fromsaid application and release pipe to close the connected end of suchpipe.

ANDREW T. GORMAN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

